I just bought a freshly rebuilt tranny out of a '91 small schoolbus. I also got the TCM from it.....still have to get a harness. (The owner of the junkyard had this tranny rebuilt last year by a local engine builder/racer).

From what I understand, the diesel's had a 'stand-alone' harness. The one in this bus appears to integrate with the 6.2l engine.

I bought this with the idea of using it in a carb'd gas application.

Any idea if the harness that's in this bus will work to control the tranny? Or do I need to get a harness elsewhere?

Appreciate any help - Thanks!!

It should work, you'll just have to pick the engine wires out and then tape it back up. You will need to leave the CTS and TPS in the harness though, these you'll need along with a tach setup to work with it. The 4L80 ECM used the TPS on the IP and the CTS along with th tach output sensor mounted on the oil pump drive to control the shifts.

It should work, you'll just have to pick the engine wires out and then tape it back up. You will need to leave the CTS and TPS in the harness though, these you'll need along with a tach setup to work with it. The 4L80 ECM used the TPS on the IP and the CTS along with th tach output sensor mounted on the oil pump drive to control the shifts.

I had a feeling the oil pump drive sensor would need to be used for something. On the CTS, I ended up unplugging several sensors (single wires) that appeared to be for coolant. Was there more than one, or would those have been something else?

Will a regular tach splice into that tach output sensor wiring? Or will I need something special? How many pulses per rev. does the factory use?

Your help is greatly appreciated!!:cool: